Protesters hold signs during an anti-coup protest on the second day of Thailand's military coup May 24, 2014, in Bangkok. / Paula Bronstein, Getty Images

by Tom Vanden Brook, USA TODAY

by Tom Vanden Brook, USA TODAY

WASHINGTON - The Pentagon announced Saturday it is suspending exercises with Thailand's military and called on officials to restore democratic rule after a bloodless coup there on Thursday.

The Defense Department also canceled a series of events planned with the Thai military. Meanwhile, the crisis in Thailand deepened Saturday as the military junta began detaining academics. It is already holding members of the government, including Prime Minister Yingluck Shinawatra and some protesters.

"As we have made clear, it is important that the Royal Thai Armed Forces end this coup and restore to the people of Thailand both the principles and the process of democratic rule, including a clear path forward to elections," Rear Adm. John Kirby, Pentagon press secretary, said in a statement Saturday.

"While we have enjoyed a long and productive military-to-military relationship with Thailand, our own democratic principles and U.S. law require us to reconsider U.S. military assistance and engagements."

The Pentagon also canceled a visit in June to Thailand by U.S. Pacific Fleet commander Adm. Harry Harris.

"We will continue to review additional engagements as necessary until such time that events in Thailand no longer demand it," Kirby said. "We urge the Royal Thai Armed Forces to act in the best interests of their fellow citizens by ending this coup and restoring the rule of law and the freedoms assured those citizens through democratic principles."

There are about 700 U.S. sailors and Marines in Thailand, a close U.S. military ally. They had been taking part in annual naval exercises known as the Cooperation Afloat Readiness and Training.

On Thursday, Gen. Raymond Odierno, the Army chief of staff, contacted his Thai counterpart, said Kirby, who characterized the conversation as constructive but did not elaborate during a Friday briefing.

The military seized power after months of street protests and a political standoff between elected officials and elite Thai families. Protests continued Saturday, but the Associated Press reported that the military had not moved against demonstrators.

The joint military exercises have become increasingly important in recent years as China has grown more assertive in the region. U.S. allies in the region have looked to the Pentagon for reassurance. Last month, U.S. and Philippine leaders signed an agreement to enhance military cooperation, including a focus on "maritime security." The Philippine military is also involved in this year's military exercises.

Defense Secretary Chuck Hagel is scheduled to visit the region as part of a trip beginning Wednesday. He will take part in talks with ministers of defense from Southeast Asia.